Coaming for a hatch opening



May 12, 1970 u. s. l. NORDH 3,511,205

COAMING FOR A HATCH OPENING Filed May 22, 1968 FIG.1

INVENTOR. U/f June Ivar Nordh A'L'Eorne s United States Patent Office 3,511,205 Patented May 12, 1970 3,511,205 COAMING FOR A HATCH OPENING Ulf Sune Ivar Nordh, Goteborg, Sweden, assignor to Associated Cargo Gear AB, Goteborg, Sweden, a corporation of Sweden Filed May 22, 1968, Ser. No. 731,009

Claims priority, application Sweden, June 26, 1967,

9,076/ 67 Int. Cl. B63b 3/54, 9/12 US. Cl. 114-201 2 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION A ship is during the voyage subjected to severe stresses. The hogging and the sagging stresses will cause noticeable longitudinal deformations of the hull and the corresponding strains in the top part of the hull must mainly be taken care of by the deck structure. Big problems will arise in connection with the hatch openings, especially with the large sized openings nowadays utilized in ships. The stresses in the deck will be transferred to the coaming surrounding the opening, and the upper part of the coaming will be deformed in the same manner as the deck. The cover is by itself a rigid structure which does not follow this deformation freely. This means that the packings between the hatch cover and the coaming are continuously subjected to wear. These relative movements will also bring about increased strains in the latching members in such a manner that it is diflicult to maintain a satisfactory sealing.

According to the present invention it is now proposed that the coaming, at least along the longitudinal sides of the opening, shall be made from corrugated plates arranged With the corrugation standing in the vertical direction. The longitudinal sides of the coaming will in this manner only to a very small degree take part in the transfer of stresses acting in the longitudinal direction of the ship, and the movements in the joint between the upper edge of the coaming and the cover will be reduced to a minimum.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows schematically a perspective view of a hatch opening surrounded by a coaming having corrugated longitudinal sides.

FIG. 2 shows a section through the side of the coaming and the corresponding part of the cover.

DESCRIPTION OF THE PREFERRED EMBODIMENT The ships deck 1 is provided with a number of hatch openings 2. Each opening is surrounded by a coaming, the longitudinal sides 3 of which is made from corrugated plates, where the corrugations are arranged standing in the vertical direction. These sides of the coaming are mounted on the deck immediately outside the opening and are welded to the deck in such a manner that the deck plating will form a straight border line towards the opening. The flutes in the side of the coaming are upwardly covered by a flange member 4, which in the manner best illustrated in FIG. 2 is provided with an outwardly directed ledge 5 adapted to cooperate with a packing 6 fitted to the cover. The transverse sides 7 of the coaming may be designed in similar manner, but as the bending stresses in the transverse direction are not so marked as in the longitudinal direction it is possible in the transverse sides to utilize ordinary flat plates strengthened in the usual manner by means of brackets or the like.

The opening is adapted to be closed by means of a cover 8 of arbitrary known type, in FIG. 1 indicated as consisting of a single section only. This extends across the opening and packings 6 fitted thereto cooperate as above mentioned with the ledges 5 in the coaming. The necessary latching members 9 are preferably located in openings in the flange member 4 arranged in connection to flutes 10 being open outwards.

What I claim is:

1. Apparatus for covering a hatch opening in a ships deck, which comprises:

a coaming, having two opposed longitudinal sides and two opposed transverse sides, fixed to the deck and surrounding sadi hatch opening,

at least the longitudinal sides of the coaming being formed from corrugated plates arranged with the corrugations standing in vertical position;

a cover member removably resting on said coaming and adapted to close said hatch opening, said cover member having a first sealing means;

a horizontally arranged flange member extending along the upper edge of each of said longitudinal sides, said flange member having at least the same breadth as the depth of said corrugations and so fixed to said longitudinal sides as to close the upwardly directed ends of the flutes of said corrugations,

said flange member being provided at its upper surface with a second sealing means complementary to and cooperating with said first sealing means when said cover is in closed position over said hatch openmg.

2. A coaming as claimed in claim 1 in which latching members are fitted into openings in the flange member arranged in connection to outwardly open flutes in the corrugated plate.

References Cited UNITED STATES PATENTS 3,104,643 9/1963 Vallet 114 202 3,164,403 1/1965 Jerome et a1. 114-203 XR 3,183,872 5/1965 McLaughlin 114 201 ANDREW H. FARRELL, Primary Examiner 

